 /*******************************************************************************
  * Copyright (c) 2000, 2006 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.ui.actions;

 import org.eclipse.core.resources.IProject;
 import org.eclipse.core.resources.IResource;
 import org.eclipse.core.runtime.Assert;
 import org.eclipse.core.runtime.IAdaptable;
 import org.eclipse.jface.viewers.IStructuredSelection;
 import org.eclipse.swt.widgets.Shell;
 import org.eclipse.ui.PlatformUI;
 import org.eclipse.ui.internal.ide.IDEWorkbenchMessages;
 import org.eclipse.ui.internal.ide.IIDEHelpContextIds;
 import org.eclipse.ui.views.markers.internal.DialogTaskProperties;

 /**
  * Standard action for adding a task to the currently selected file
  * resource(s).
  * <p>
  * This class may be instantiated; it is not intended to be subclassed.
  * </p>
  * @since 2.1
  */
 public class AddTaskAction extends SelectionListenerAction {
     /**
      * The id of this action.
      */
     public static final String ID = PlatformUI.PLUGIN_ID + ".AddTaskAction";//$NON-NLS-1$

     /**
      * The shell in which to show any dialogs.
      */
     private Shell shell;

     /**
      * Creates a new instance of the receiver.
      *
      * @param shell shell to use to show any dialogs
      */
     public AddTaskAction(Shell shell) {
         super(IDEWorkbenchMessages.AddTaskLabel);
         setId(ID);
         this.shell = shell;
         Assert.isNotNull(shell);
         setToolTipText(IDEWorkbenchMessages.AddTaskToolTip);
         PlatformUI.getWorkbench().getHelpSystem().setHelp(this,
                 IIDEHelpContextIds.ADD_TASK_ACTION);
     }

     private IResource getElement(IStructuredSelection selection) {
         if (selection.size() != 1) {
             return null;
         }

         Object element = selection.getFirstElement();
         IResource resource = null;
         if (element instanceof IResource) {
             resource = (IResource) element;
         }
         if (element instanceof IAdaptable) {
             resource = (IResource) ((IAdaptable) element)
                     .getAdapter(IResource.class);
         }

         if (resource != null && resource instanceof IProject) {
             IProject project = (IProject) resource;
             if (project.isOpen() == false) {
                 resource = null;
             }
         }
         return resource;
     }

     /* (non-Javadoc)
      * Method declared on IAction.
      */
     public void run() {
         IResource resource = getElement(getStructuredSelection());
         if (resource != null) {
             DialogTaskProperties dialog = new DialogTaskProperties(shell);
             dialog.setResource(resource);
             dialog.open();
         }
     }

     /**
      * The <code>AddTaskAction</code> implementation of this
      * <code>SelectionListenerAction</code> method enables the action only
      * if the selection contains a single resource and the resource is
      * not a closed project.
      *
      * @param selection the selection to update the enabled state for
      */
     protected boolean updateSelection(IStructuredSelection selection) {
         return super.updateSelection(selection)
                 && getElement(selection) != null;
     }
 }

